Students often ask me to recommend books that would be good for someone with an interest in Clinical Psychology to read. Whilst you can't learn to be a Clinical Psychologist just by reading books (a professional training and ongoing supervision are both essential), it is important to read widely in order to broaden your understanding of people and their problems.
Inside Lives, by Margot Waddell, is a text suitable for Masters level students and final year undergraduates with a serious interest in the topic of personality development, both healthy and pathological. Written from a psychoanalytic perspective, Inside Lives elegantly lays out a predominantly post-Kleinian account of the way in which our closest relationships influence our capacity to manage distress and to bear reality, however difficult it may be.
This is a book that I and many of my colleagues return to again and again. Ironically, for a book about personality development across the lifespan, it never gets old!